JESSICA Simpson (above) is dropping weight faster than she realizes. Celebrating her hairstylist Ken Paves‘ birthday Wednesday night at Beso in Hollywood, “she didn’t eat much, because she’s been dieting since her split from Tony Romo,” said our source. So after two drinks, the 5-foot-3 star “got tipsy really fast.” Photos show a bleary, but svelte, Simpson holding onto Paves as they exited. Simpson’s rep told us, “She was out celebrating Ken’s birthday, and now she’s getting ready to leave the country to film her docu-series for VH1.”